Fitting for concrete slab



July 19, 1960 V. 5. MURRAY FITTING FOR CONCRETE SLAB Filed Sept. 20,1957 INVENTOR Vlcroz 5. Mme/24y ATTORNEY Stat s FOR CONCRETE SLAB VictorS. Murray, 357 Courtleigh Blvd., Toronto, Ontario, Canada This inventionrelates to fittings for electrical wire and the like.

It is common practice to employ cellular concrete slabs in the formationof doors or ceilings particularly in industrial commercial and publicbuildings. The passages in such slots are frequently employed for thereception of electrical and other service wires. The tapping of suchslabs to .provide access to the wire containing passages and theprovision of an acceptable fitting through which the wires may be led isdifficult and expensive. Usually, a large hole is drilled through theslab into the passage therein, a tubular fitting positioned in theopening and the remainder of the opening filled with grouting orconcrete to secure the fitting in place in the slab. In addition tobeing a costly operation, it is time-consuming and wasteful.

It is an object of this invention to provide a tubular fitting forpassage of wires from a cellular concrete slab which is simple instructure and convenient to manufacture, and which may be placeddirectly in a drilled hole in said slab and rigidly positioned thereinwithout the use of concrete, grouting or the like.

The fitting, in accordance with the invention, comprises a tubularmember having a first ring in screwthreaded engagement with one endthereof, and a wing extending laterally from said first ring, and asecond ring encircling said tubular member and having a shoulderengageable with said first ring, said second ring also having alaterally extending wing and being rotatable with respect to saidtubular member to place said wings in overlapping position or indiametrically opposed relation.

The fitting will be described with reference to the accompanyigndrawing, in which Figure l is a side elevation, partly in section, of afitting in accordance with the invention,

Figure 2 is a side elevation of the fitting in a different positionthereof, and

Figure '3 is a plan view of the fitting.

In the drawing, 1 is a fitting in accordance with the invention andcomprises an externally threaded tubular member 2, and a ring 3 inscrewqthreaded engagement with one end thereof and having an internalannular rib 3a adapted to overlie the end edge of member 2. Ring 3 has alaterally extending wing 5. As shown, wing 5 has a curved top surface 6which projects slightly upwardly from the adjacent plane end surface 7of the ring but merges gradually thereinto, and a fiat bottom surface 8which is in substantially the same plane as end surface 7. It will beapparent that an annular shoulder 9 is constituted by the lower end ofthe ring 3.

A second ring 10 encircles the first ring 3 with just sufiicientclearance to permit ease of rotation of ring 10 with respect to ring 3.Ring .10 has an internally extending annular shoulder 11 at one end forengagement with the annular shoulder 9. Ring .10 has a wing 12 extendinglaterally from its other end. Wing 12 also has a curved top surface 13which projects slightly upwardly Patented July .19, 1960 7 from theadjacent plane endsurface 14 0f the ring but merges gradually thereinto,and a fiat bottom sur face 15 which. is in substantially the same planeas surface 14. 1

In use, the fitting is adapted to be applied to aconcrete slab 16-having a passage 17 therein to which access is desired from the outerface 18 thereof. A hole 1-9 -is drilled through the slab from face .18,such hole being of a diameter approximately equal to or slightly largerthan the exterior diameter of ring 10. The ring 10 is rotated withrespect to tubular member 2 to place wing 12 in underlapping relation towing 5. In this position of the fitting, by slightly tilting it, thering 3 with encircling ring 10 may be placed in the hole 19 with thewings 5 and 12 projecting laterally of the edge thereof within thepassage 17. Such placing of the rings is rendered possible because thewidth of each ring, as clearly shown in 'Figure 3, is not greater thanthe external diameter of ring 10. The tubular member 2 with ring 3 isnow rotated relatively to ring 10 to place wing 5 in diametricallyopposite relation to wing 12, as shown in Figure l. Preferably, the ring10 carries, on its interior surface, a stop 10a which is adapted toenter a recess 10b in the shoulder 9 when the wings are in diametricallyopposite relation. A locknut 20 is now applied to the lower end portion4 of tubular member 2 to lock the ring in such position to member 2. Itwill be observed that, in the latter position .of wings 5 and 12 theirbottom surfaces 8 and 15 are in substantially the same plane and arearranged to seat upon the surface of passage 17 adjacent hole 19, theaxial extent of ring 10 and ring 3 with locknut 20 being approximatelyequal to the depth of the hole 19 whereby the end surface of locknut 20is about flush with the face 18 of the slab.

An outlet box, fixture or like device 21 may now be applied to thefitting and secured thereto as by an additional locknut 22, the boxengaging the outer face 18 of the slab, whereby the entire assembly isfir-mly secured in position. A ring 23 is applied to the outer end ofthe tubular member to complete the fitting.

I claim:

1. A building slab fitting for passage of electrical wires a laterallyextending wing, said wing having a slab-engageable surface lying in .aplane spaced outwardly from the plane of said end edge of said tubularmember, and a second ring encircling said first ring and having anannular shoulder engaging the end edge of said first ring, said secondring also having a wing extending laterally therefrom and beingrotatable to vary the position of said wings with respect to each other,said second wing having a slab-engageable surface lying in a planespaced outwardly from the plane of said end edge of said tubular member,each said wing having a width not greater than the external diameter ofsaid second. ring, and means for locking said rings against rotationwith respect to said tubular member.

2. In a building slab having a passage therein, a fitting providingaccess to said passage for electrical wires and the like-comprising anexternally threaded tubular memher, a ring threadedly mounted on .oneend portion thereof and having an annular rib engageable with the endedge of said tubular member, said ring also having a laterally extendingwing, said wing having a slab-engageable surface lying in a plane spacedoutwardly from the plane of said end edge of said tubular member, and asecond ring encircling said firs-t ring and having an annular shoulderengageable with the end edge of said first ring, said second ring alsohaving a wing extending laterally 3 therefrom and being rotatable tovary the position of References Cited in the file of this patent saidwings with respect to each other, said second wing having aslab-engageable surface lying in a plane spaced UNITED STATES PATENTSoutwardly from the plane of said end edgeof saidtu: 1,785,709 CampauDec. 16, 1930 bular member, each said wing having a Width not greater 51,878,579 Gober Sept. 20, 1932 than the external diameter of said secondring, said slab 2,403,247 Sullivan July 2, 1946 having a hole extendinginto said passage, one end of a said fitting with said wings beinginsertable through said FOREIGN PATENTS hole when said wings are inunderlapping relation to 55 France June 20 1 4 each other, and means forlocking said rings to said tu- 10 bular member.

